Flexible touch display is a very competitive display technology in the future. One of the great advantages of the flexible touch display device is that it can be bent so that a larger display area can be obtained while occupying less space and being easily portable and applicable. The conventional flexible touch display device generally adopts a flexible substrate, and sequentially fabricates elements such as a thin film transistor and an organic light-emitting diode on a flexible substrate, and finally adds a polarizer, a flexible touch panel and a cover glass.
In order to realize the flexible touch panel to be flexible, the touch wire in the flexible touch panel should be able to endure bending and prevent the problem that the touch wire breaks during repeated bending. It is important to ensure that the electrical properties of the touch control wire are not affected by the physical deformation or are less affected by the touch effect. Therefore, the structural strength and reliability of the touch control wire are very important.
Under the existing technical conditions, due to the characteristics of the touch wire material and the structure of the touch panel, there are still some problems in making a flexible touch panel.
In terms of material, if the material of the touch control wire is Indium Tin Oxide (ITO), although the light transmittance of ITO is good, the bending resistance is poor; if the material of the touch control wire is silver nanowire (AgNW), silver (Ag), silver alloy, etc., the bending resistance is improved, but the light transmittance is poor.
From a structural point of view, please refer to FIG. 1 to FIG. 4 at the same time, the existing flexible touch panel generally adopts the structure of a single-layer bridging and includes a plurality of first touch electrodes 300 disposed in the first direction and parallel to each other, and a plurality of second touch electrodes 500 disposed in the same layer as the first touch electrodes 300 and arranged in the second direction perpendicular to the first direction and parallel to each other. The first touch electrode 300 includes a plurality of first touch electrode blocks 301. Two adjacent ones of the first touch electrode blocks 301 are connected by a connecting strap 302 extending from the first touch electrode block 301. The second touch electrode 500 includes a plurality of second touch electrode blocks 501. Two adjacent ones of the second touch electrode blocks 501 are connected by a conductive bridge 502 crossing the connecting strap 302. An insulating block 400 is disposed between the connecting strap 302 and the conductive bridge 502. Two sides of the conductive bridge 502 respectively contact with a second touch electrode block 501 through a via hole 401 penetrating through the insulating block 400. Further, the conductive bridge 502 is a strap-shaped entity, corresponding to a single connecting wire. There are two prominent problems with such a structure. First, the conductive bridge 502 contacts the second touch electrode 501 only through a single via hole 401, the contact area is small, and the contact resistance is large, which may lead to poor conduction. Second, when the touch panel is bent, the conductive bridge 502 corresponding to a single connecting wire is easily broken by the influence of bending stress, resulting in disconnection and low reliability.